<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>倒计时</title>
    <style>
        body,html{
            margin: 0;
            padding: 0;
        }
        body{
            background-color: #494A5F;
        }
        div{
            margin-top: 50px;
            text-align: center;
            background-color: #3D4444;
            color: white;
            height: 200px;
            line-height: 200px;
            font-size: 35px;
        }
    </style>
</head>
<body>
    <script src="js/countdown.js"></script>
</body>
</html>